Table of ContentsView AllTable of ContentsTypesSymptomsCausesDiagnosisTreatment
Table of ContentsView All
View All
Table of Contents
Types
Symptoms
Causes
Diagnosis
Treatment
Learn about the different types of latent infections, including causes, treatment methods, and more.
Thomas Deerinck, Ncmir / Science Photo Library / Getty Images
Types of Latent Infections
Different types of organisms can intrude on the body and cause a latent infection. Although some types of latent infections are more common than others, the organisms involved in all types are usually inactive and cause no symptoms.
Viral Latent Infections
Herpes Simplex Virus (HSV)
Commonly known asherpes, herpes simplex virus (HSV) can causesoreson or in the mouth or genitals. HSV is categorized into two types: HSV-1 and HSV-2. HSV-1 mainly affects the mouth and face, and HSV-2 generally affects the genital area.
After the initial infection, the herpes virus stays dormant in the body for a lifetime and can cause symptoms like cold sores or genital warts from time to time. However, the virus rarely causes serious health risks for those who are healthy and nonpregnant, and symptoms typically clear with or without treatment.
Varicella Zoster Virus (VZV)
Varicella-zoster virus (VZV)is the virus that causes the common childhood disease known aschickenpox (varicella). After a chickenpox infection, VZV can remain in the body for a lifetime and potentially reactivate and cause the blistering condition known as shingles in older adults.
Disease from VZV infection generally does not cause serious health problems and can be treated with medication and protected against with vaccination.
Human Immunodeficiency Virus (HIV)
Human immunodeficiency virus (HIV), the virus known to affect the immune system and develop intoacquired immunodeficiency syndrome (AIDS), can infect immune system cells and become latent. HIV latency can occur even when a person infected with the virus is receiving standard HIV treatment known asantiretroviral therapy (ART).
HIV latency is a major reason why HIV cannot entirely be cured. But research is ongoing to find ways for medications and the immune system to notice and terminate latent HIV-infected cells.
Bacterial Latent Infections
While TB bacterial infection can lead to sickness, the bacterium can live in the body and remain latent for a lifetime. If TB bacteria become active, it can lead to TB, which can be serious if not treated properly. However, the correct use of vaccines and medicines can help prevent or cure most TB cases.
Parasitic Latent Infections
Parasitesare organisms that live in or on another organism to survive. The parasite known asToxoplasma gondiiis the most common parasite that infects the population.
When active in the body,T. gondiican cause the condition known astoxoplasmosis. But the parasite can become latent and live in the body for a lifetime. Toxoplasmosis disease can resolve without treatment in those who are healthy and nonpregnant but can be treated with medications if it causes illness or poses health risks.
Atapeworm infectionis another type of parasitic infection that is sometimes considered latent. An infection can occur from swallowing the larvae of a tapeworm when contaminated food or fingers are put in the mouth.
These larvae can form cysts in body tissues that remain for multiple years, potentially causing a condition known as cysticercosis. With cysticercosis, the cysts formed from the larvae die and irritate the tissues around them, causing them to swell. While some people may not need treatment for cysticercosis, medications are available if the condition is too bothersome.
Latent Infection Symptoms
Typically, latent infections cause no noticeable symptoms. Symptoms usually develop when dormant organisms in the body become active and cause disease. Symptoms may vary from one disease to another, but common ones include:
An Overview of Infection
Know that just because an infection is not causing symptoms doesn’t mean it’s latent. Some organisms can be active at a small scale and cause little to no symptoms but can still be transmissible to other people or surfaces.
Since latent infections are usuallyasymptomatic, laboratory testing is a standard measure used to form a diagnosis. Lab tests help identify the type of organism that’s causing an infection, which paves the way for knowing what to do for treatment if necessary. Some of the most common lab tests for latent infections include:
If the test is positive, a chestx-raymay be ordered to see where abnormalities or lesions are present in the lungs before using other diagnostic measures.
For those in good health, a latent infection may not need treatment. A healthy immune system is generally able to clear many types of infections or prevent an inactive organism from becoming active.
Treatment may be needed in those who are pregnant or have weakened immune systems. For example, research shows that those who are pregnant and have latent TB infection have elevated pregnancy and birth complication risks if they don’t receive treatment.
And for those with weakened immune systems, a latent infection poses the risk of becoming an active infection and causing severe illness.
Treatment depends on the type of infection, especially when a latent infection becomes an active one. Treating TB with antibiotics like isoniazid (INH) and Priftin (rifapentine) is common,while an antiparasitic like Daraprim (pyrimethamine) is typically used for a parasitic disease like toxoplasmosis.
ART, which includes medicines like nucleoside reverse transcriptase inhibitors (NRTs), is used for HIV treatment,while antiviral medications like Zovirax (acyclovir) are used to treat HSV and VZV.
Summary
A Word From Verywell
It can be difficult to know if you have a latent infection, as such infections typically present no symptoms. However, if you learned that you were in close vicinity or in contact with someone with an infection that can become latent, such as TB, you should visit your healthcare provider to get screened.
Doing so can help determine if you have an infection and if treatment is needed, which is important if you are pregnant or have an autoimmune disorder like HIV.
Frequently Asked QuestionsPersistent infection is when an organism is continually active or replicating in the body, whereas a latent infection is when an organism is inactive.Manysexually transmitted infections (STIs)go through a latency stage, where those infected areasymptomatic. However, not all infections are truly latent at this stage.For an STI like herpes, in the latency stage, the infection can activate enough for asymptomatic shedding, which is when a person showing no symptoms spreads viral particles to others or into the environment through physical contact, coughing, sneezing, speaking, etc.
Frequently Asked Questions
Persistent infection is when an organism is continually active or replicating in the body, whereas a latent infection is when an organism is inactive.
Manysexually transmitted infections (STIs)go through a latency stage, where those infected areasymptomatic. However, not all infections are truly latent at this stage.For an STI like herpes, in the latency stage, the infection can activate enough for asymptomatic shedding, which is when a person showing no symptoms spreads viral particles to others or into the environment through physical contact, coughing, sneezing, speaking, etc.
Manysexually transmitted infections (STIs)go through a latency stage, where those infected areasymptomatic. However, not all infections are truly latent at this stage.
For an STI like herpes, in the latency stage, the infection can activate enough for asymptomatic shedding, which is when a person showing no symptoms spreads viral particles to others or into the environment through physical contact, coughing, sneezing, speaking, etc.
19 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Larragoite ET, Spivak AM.Down but not out.Elife. 2019;8:e53363. doi:10.7554/eLife.53363Centers for Disease and Control and Prevention.About genital herpes.Centers for Disease Control and Prevention.Chickenpox (Varicella).Dahabieh MS, Battivelli E, Verdin E.Understanding HIV latency: the road to an HIV cure.Annu Rev Med. 2015;66:407-421. doi:10.1146/annurev-med-092112-152941Centers for Disease Control and Prevention.Ending the global tuberculosis epidemic.Centers for Disease Control and Prevention.Inactive tuberculosis.Flegr J, Prandota J, Sovičková M, Israili ZH.Toxoplasmosis–a global threat. Correlation of latent toxoplasmosis with specific disease burden in a set of 88 countries.PLoS One. 2014;9(3):e90203. doi:10.1371/journal.pone.0090203Centers for Disease Control and Prevention.Toxoplasmosis.Centers for Disease Control and Prevention.Parasites — cysticerosis.Centers for Disease Control and Prevention.Parasites.Centers for Disease Control and Prevention.How TB spreads.Drexler M; Institute of Medicine (US).What you need to know about infectious disease.Centers for Disease Control and Prevention.Tuberculosis: testing & diagnosis.Miele K, Bamrah Morris S, Tepper NK.Tuberculosis in pregnancy.Obstet Gynecol. 2020;135(6):1444-1453. doi:10.1097/AOG.0000000000003890Centers for Disease Control and Prevention.TB and HIV coinfection.Centers for Disease Control and Prevention.Treatment for latent TB infection and TB disease.MedlinePlus.HIV medicines.LibreTexts: Biology.General categories of viral infections.Johnston C, Corey L.Current concepts for genital herpes simplex virus infection: diagnostics and pathogenesis of genital tract shedding.Clin Microbiol Rev. 2016;29(1):149-161. doi:10.1128/CMR.00043-15Additional ReadingCohn LB, Silva IT, Oliveira TY, et al.HIV-1 integration landscape during latent and active infection.Cell. 2015;160(3):420-32. doi:10.1016/j.cell.2015.01.020Siliciano JD, Siliciano RF.Recent developments in the search for a cure for HIV-1 infection: targeting the latent reservoir for HIV-1.J Allergy Clin Immunol. 2014;134(1):12-9. doi:10.1016/j.jaci.2014.05.026
19 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Larragoite ET, Spivak AM.Down but not out.Elife. 2019;8:e53363. doi:10.7554/eLife.53363Centers for Disease and Control and Prevention.About genital herpes.Centers for Disease Control and Prevention.Chickenpox (Varicella).Dahabieh MS, Battivelli E, Verdin E.Understanding HIV latency: the road to an HIV cure.Annu Rev Med. 2015;66:407-421. doi:10.1146/annurev-med-092112-152941Centers for Disease Control and Prevention.Ending the global tuberculosis epidemic.Centers for Disease Control and Prevention.Inactive tuberculosis.Flegr J, Prandota J, Sovičková M, Israili ZH.Toxoplasmosis–a global threat. Correlation of latent toxoplasmosis with specific disease burden in a set of 88 countries.PLoS One. 2014;9(3):e90203. doi:10.1371/journal.pone.0090203Centers for Disease Control and Prevention.Toxoplasmosis.Centers for Disease Control and Prevention.Parasites — cysticerosis.Centers for Disease Control and Prevention.Parasites.Centers for Disease Control and Prevention.How TB spreads.Drexler M; Institute of Medicine (US).What you need to know about infectious disease.Centers for Disease Control and Prevention.Tuberculosis: testing & diagnosis.Miele K, Bamrah Morris S, Tepper NK.Tuberculosis in pregnancy.Obstet Gynecol. 2020;135(6):1444-1453. doi:10.1097/AOG.0000000000003890Centers for Disease Control and Prevention.TB and HIV coinfection.Centers for Disease Control and Prevention.Treatment for latent TB infection and TB disease.MedlinePlus.HIV medicines.LibreTexts: Biology.General categories of viral infections.Johnston C, Corey L.Current concepts for genital herpes simplex virus infection: diagnostics and pathogenesis of genital tract shedding.Clin Microbiol Rev. 2016;29(1):149-161. doi:10.1128/CMR.00043-15Additional ReadingCohn LB, Silva IT, Oliveira TY, et al.HIV-1 integration landscape during latent and active infection.Cell. 2015;160(3):420-32. doi:10.1016/j.cell.2015.01.020Siliciano JD, Siliciano RF.Recent developments in the search for a cure for HIV-1 infection: targeting the latent reservoir for HIV-1.J Allergy Clin Immunol. 2014;134(1):12-9. doi:10.1016/j.jaci.2014.05.026
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
Larragoite ET, Spivak AM.Down but not out.Elife. 2019;8:e53363. doi:10.7554/eLife.53363Centers for Disease and Control and Prevention.About genital herpes.Centers for Disease Control and Prevention.Chickenpox (Varicella).Dahabieh MS, Battivelli E, Verdin E.Understanding HIV latency: the road to an HIV cure.Annu Rev Med. 2015;66:407-421. doi:10.1146/annurev-med-092112-152941Centers for Disease Control and Prevention.Ending the global tuberculosis epidemic.Centers for Disease Control and Prevention.Inactive tuberculosis.Flegr J, Prandota J, Sovičková M, Israili ZH.Toxoplasmosis–a global threat. Correlation of latent toxoplasmosis with specific disease burden in a set of 88 countries.PLoS One. 2014;9(3):e90203. doi:10.1371/journal.pone.0090203Centers for Disease Control and Prevention.Toxoplasmosis.Centers for Disease Control and Prevention.Parasites — cysticerosis.Centers for Disease Control and Prevention.Parasites.Centers for Disease Control and Prevention.How TB spreads.Drexler M; Institute of Medicine (US).What you need to know about infectious disease.Centers for Disease Control and Prevention.Tuberculosis: testing & diagnosis.Miele K, Bamrah Morris S, Tepper NK.Tuberculosis in pregnancy.Obstet Gynecol. 2020;135(6):1444-1453. doi:10.1097/AOG.0000000000003890Centers for Disease Control and Prevention.TB and HIV coinfection.Centers for Disease Control and Prevention.Treatment for latent TB infection and TB disease.MedlinePlus.HIV medicines.LibreTexts: Biology.General categories of viral infections.Johnston C, Corey L.Current concepts for genital herpes simplex virus infection: diagnostics and pathogenesis of genital tract shedding.Clin Microbiol Rev. 2016;29(1):149-161. doi:10.1128/CMR.00043-15
Larragoite ET, Spivak AM.Down but not out.Elife. 2019;8:e53363. doi:10.7554/eLife.53363
Centers for Disease and Control and Prevention.About genital herpes.
Centers for Disease Control and Prevention.Chickenpox (Varicella).
Dahabieh MS, Battivelli E, Verdin E.Understanding HIV latency: the road to an HIV cure.Annu Rev Med. 2015;66:407-421. doi:10.1146/annurev-med-092112-152941
Centers for Disease Control and Prevention.Ending the global tuberculosis epidemic.
Centers for Disease Control and Prevention.Inactive tuberculosis.
Flegr J, Prandota J, Sovičková M, Israili ZH.Toxoplasmosis–a global threat. Correlation of latent toxoplasmosis with specific disease burden in a set of 88 countries.PLoS One. 2014;9(3):e90203. doi:10.1371/journal.pone.0090203
Centers for Disease Control and Prevention.Toxoplasmosis.
Centers for Disease Control and Prevention.Parasites — cysticerosis.
Centers for Disease Control and Prevention.Parasites.
Centers for Disease Control and Prevention.How TB spreads.
Drexler M; Institute of Medicine (US).What you need to know about infectious disease.
Centers for Disease Control and Prevention.Tuberculosis: testing & diagnosis.
Miele K, Bamrah Morris S, Tepper NK.Tuberculosis in pregnancy.Obstet Gynecol. 2020;135(6):1444-1453. doi:10.1097/AOG.0000000000003890
Centers for Disease Control and Prevention.TB and HIV coinfection.
Centers for Disease Control and Prevention.Treatment for latent TB infection and TB disease.
MedlinePlus.HIV medicines.
LibreTexts: Biology.General categories of viral infections.
Johnston C, Corey L.Current concepts for genital herpes simplex virus infection: diagnostics and pathogenesis of genital tract shedding.Clin Microbiol Rev. 2016;29(1):149-161. doi:10.1128/CMR.00043-15
Cohn LB, Silva IT, Oliveira TY, et al.HIV-1 integration landscape during latent and active infection.Cell. 2015;160(3):420-32. doi:10.1016/j.cell.2015.01.020Siliciano JD, Siliciano RF.Recent developments in the search for a cure for HIV-1 infection: targeting the latent reservoir for HIV-1.J Allergy Clin Immunol. 2014;134(1):12-9. doi:10.1016/j.jaci.2014.05.026
Cohn LB, Silva IT, Oliveira TY, et al.HIV-1 integration landscape during latent and active infection.Cell. 2015;160(3):420-32. doi:10.1016/j.cell.2015.01.020
Siliciano JD, Siliciano RF.Recent developments in the search for a cure for HIV-1 infection: targeting the latent reservoir for HIV-1.J Allergy Clin Immunol. 2014;134(1):12-9. doi:10.1016/j.jaci.2014.05.026
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